Old school SBC/BBC to LS family comparo.

Discussion in 'High Tech Retrofits' started by newschool72, Sep 23, 2013.

  1. newschool72

    newschool72 Veteran Member

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    Im with you on the LS1. Its been a while sense the first LS was discontinued and all the sensors and rubber crap will be trashed from sitting so long. If its a simple carb setup, I would feel differently about the purchase.
    The 6.0s and especially the 6.2 are more desirable for the reason you stated. The L92/LS3 heads are a great bargain and the bigger bore is a requirement to run them. That in no way discounts the smaller LS versions, its just that for really big numbers with great street ability and factory parts, the 6.0 (4.00" bore)would be the smallest bore I would go with personally .
     
  2. reedld

    reedld Veteran Member

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    73 L92,

    Off topic a bit...I see you are from Minnesota...did you have a late 70's Red Camaro for sale on ls1tech? When I was first looking to do a swap, I came across one for sale. It was a gorgeous car.

    Leon
     
  3. sbca96

    sbca96 Veteran Member

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    ...And what makes financial sense. And has others in pollution controlled States
    will agree .. what I CAN do. When you roll those together it will equal LT1. Cost
    to do a smog legal LSx swap is up there.

    Once I get the fuel tank back in, and the restriction out of the exhaust, we will
    see how badly I lose against others on this forum. So far I have been quite a
    lot more forthcoming with results than others here. Some will post 500+ horse
    power numbers and no actual speeds to back it up.

    At some point the return doesn't justify the means, traction will be limiting just
    how much of that 550 hp actually gets to the pavement. Rolling starts do not
    really count in my book, but I will try and match Leonards when I am back onto
    the road ... hopefully this weekend.

    Tom
     
  4. newschool72

    newschool72 Veteran Member

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    I just checked out Leonards thread. It is a nice stock reproduction , in iron, of the LS6 from the earliest ZO6 vettes. I wish you and he were close enough to actually run them, heads up. Im not sure of his race weight, but the vette, at 3100 and change, was a mid to low 12 sec ride. Leonard should be able to knock down a solid low to mid 13 sec pass if the trans will hold up. In stock form the 2004R was built to stand up to a 120HP V6.
    Anyone got the 1/4 mile times on the early 90s LT1 vette. I would expect a spread about like the difference between the 03 ZO6 and the LT1 vette, give or take , depending on the weights of the two.

    EDIT.... I looked up the performance as tested new.....92 vette,LT1 ,6sd manual.....road and track-14.1 at 102mph
    03 vette Z06,LS6, 6sd manual....road and track- 12.4 no MPH given
    04 vette Z06,6 sd manual . GM Hightech performance-11.97 at 118mph
     
    Last edited: Oct 3, 2013
  5. sbca96

    sbca96 Veteran Member

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    Not sure what we are proving with the Corvette numbers, but yet again pick
    a low LT1 time and the fastest LS time. The 1992 LT1 was different, they had
    made improvements by 1994, and more by 1996. Not including the LT4.

    1995 Chevrolet Corvette LT1 0-60 mph 5.1 Quarter mile 13.5

    LS1 first year :
    1997 Chevrolet Corvette 0-60 mph 4.6 Quarter mile 13.1

    Reported tests from 1992-1996 range 0-60 mph at 5.0-5.7 seconds and with
    a 1/4 mile elapsed time range 13.6-14.8 seconds at 95-104 mph.

    What I was referring too was his rolling start. We couldnt get any traction on
    the sprint either, and had two people in the car. Not running headers and the
    reducer is choking the engine considerably. We also had fuel starvation toward
    the end of the 1/4 mile run. That said, we were breaking loose in 2nd on the
    upshift, but we throttled back and took the hit. He used a rolling start at the
    "brisk jog" I think he said. Thats about 5-10 mph? I was going to match that
    and see how much our 0-60 time improves. What you JUST dont get is, I am
    expecting to lose. I have WAY less money into my swap and I am running the
    base LT1 with not even a tune! His car does not have a snowballs chance in
    hell of passing smog in California.

    My thread is here :

    http://www.nastyz28.com/forum/showthread.php?t=259226

    Her best 0-60 was 6.107 seconds, not bad considering ... bugs to work out.

    We ran ONE 1/4 mile run, which was a telling 14.96 @ 96.92 miles per hour. I
    know we didnt hook as well that time, since the 0-60 on the 1/4 was 6.563.
    When you look at the Corvette numbers, we did pretty good. I also put the
    weight down as 3700, where as Leonard put 3945. I weighed ours and it was
    3660 with me in the car and a half tank fuel. Leonard was alone. We should
    be about dead even in weight, or he may be a little lighter with the 2004R. I
    know the G-tech uses weight to figure out speeds, so it is critical.

    It will also help that we have a working speedometer now! I tracked with the
    AutoXray and its slow keeping up.

    Edit : the California emissions 118 hp 305/TH350 lists a 0-60 mph 12.9 seconds
    with a 1/4 mile time at 20.1 seconds.

    Tom
     
    Last edited: Oct 4, 2013
  6. 73 L92

    73 L92 Veteran Member

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    I sold the 79 Camaro with the LS1 I think about 3 years ago. Went to St.Louis. It was a nice car. My first LS swap.
    We do the Car Craft show every year. My 73 Z28 Camaro L92/TKO 600 is a Atomic Orange. Featured in Car Craft magazine Feb 2013.
     
  7. newschool72

    newschool72 Veteran Member

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    Tom , I just did a quick search to get an idea of the differences between the only model that was offered with both engines. That was a half hearted attempt to get some kind of parallel between your car and Leonards. In no way was it meant to compare earlier corvette performance to latter.
    The point was to illustrate that it isn't a good idea to go up against an LS6 with your LT1. You are out classed and if you are within a second, Leonards car is in need of a tune. What you are doing is like comparing an old TPI 350 to your LT1 .
    Im sure you will come back with a comment something like" a second isn't that much when the cost of the build is so much lower on mine". A second is a complete blow out in a 1/4 mile race. For a second difference, if you are in the slower car, will make you wonder if you put your car in drive because you feel like you are sitting still! Ask me how I know that, been there, got the t-shirt.
    The comparison from a roll with the G meter has so many holes in it that there is no way to give any credence to the test. The g meters are never very close to actual 1/4 mile run at a track and really prove nothing. They are a decent tool to gauge differences in your car from run to run for rough tuning, but in no way are they an accurate way to compare cars. That happens at a track, side by side. And how can a run from a roll help you figure out a 0-60 run? Yes ,you will pick up considerably from your last run. 15 to 60 isn't 0-60 !
    Im just not sure at this point, well, what your point is ? You know you will loose, so what is the point of the conversation. That it is cheaper in California to put an LT1 in your car than a LS1? OK , no one is arguing that that I can tell. That you will be slower, but still run respectably? OK, I think we all agree that the LT1 is a strong engine and runs good, especially for the price . That the LS1 is only about 40-50 hp stronger in bone stock form? That is a big difference in an engine that shares the same displacement and is as good on fuel economy, if not better. Im just trying to understand your point in all of this. Maybe you can help me understand it. Help me out here.
     
  8. Todd80Z28

    Todd80Z28 Moderator Staff Member Lifetime Gold Member

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    Holy crap, Tom, this ain't rocket science. LS will of course be much stronger for two basic reasons-

    1. Cylinder head flow- Stock LT1- 210cfm intake, stock LS1- 240cfm intake, stock LS6- 260cfm intake, stock LS3- 280-290cfm intake.
    This is also why cam changes make so much more difference on LS than LT. If the head is already flowing near its potential, more cam won't have much effect. GM provided a good crate motor example-

    ZZ4 (350, L98 aluminum heads) with ZZ4 cam (208/221, .474"/.510")- 355hp
    ZZ4 with LT4 HOT Cam (218/228, .525"/.525")- 359hp
    FB385 (350, Fastburn heads) with ZZ4 cam- 385hp
    ZZ430 (350, Fastburn heads, LT4 HOT cam)- 430hp

    The same cam "found" 70hp because of the heads.

    2. Distributorless ignition- more accurate timing events can add 15-20ft lbs through the midrange and top end, and the HP that goes with it.

    LT is cheap and simple and fits where the old SBC did. LS is stronger and newer. The bench racing is silly, LT will lose every time, unless the driver sucks completely.

    This argument has gone off the rails. :confused:
     
  9. sbca96

    sbca96 Veteran Member

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    I have tried, but its obviously pointless. I give up. Everyone should have an LS
    motor because they are better in every way possible.

    Done.

    Tom
     
  10. 5spd540

    5spd540 Veteran Member Lifetime Gold Member

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    I give up. Everyone should have an LS
    motor because they are better in every way possible.
     

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